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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Caracterização e comparação de sistemas de embalagem e transporte de mamão \'Solo\' destinado ao mercado nacional. / Characterization and comparison of packaging and transport systems of Solo papaya fruits for the domestic market.

Cerqueira-Pereira, Elaine Costa 04 August 2009 (has links)
O objetivo do trabalho foi caracterizar sistemas de embalagem e transporte do mamão Solo destinado ao mercado nacional e compará-los entre si, avaliando suas influências no desempenho pós-colheita do mamão transportado do local de produção até o mercado atacadista. Inicialmente foi realizado um estudo de mercado na Companhia de Entrepostos e Armazéns Gerais de São Paulo - CEAGESP para entender a comercialização desse produto. Foram analisados mamões comercializados na CEAGESP acondicionados em caixas de papelão, transportados em caminhão refrigerado (sistema 1) e mamões acondicionados em caixas de madeira, transportados em caminhão coberto com lona (sistema 2) para identificar e caracterizar os principais danos abióticos e bióticos que ocorrem na cadeia de comercialização e para determinar a interferência de cada sistema no desempenho pós-colheita. Os mamões foram levados para o Laboratório de Pós-colheita do Departamento de Produção Vegetal da ESALQUSP mantidos a 23ºC e 80-90% UR, até o completo amadurecimento. O mamão do grupo Solo é o mais comercializado na CEAGESP e dentro desse grupo a cultivar Sunrise devido a suas qualidades organolépticas, mas o mamão Golden é o único comercializado em dois sistemas distintos de embalagem e transporte. As injúrias mecânicas detectadas foram abrasões, cortes e amassamentos em ordem decrescente de ocorrência. Verificou-se maior quantidade de frutos injuriados no sistema 2. A perda de firmeza no terceiro dia de armazenamento foi aproximadamente 42% para os frutos do sistema 1 e de 63% para os frutos do sistema 2. No quarto dia de armazenamento a atividade respiratória assumiu valores médios de 30,4 e 36,5 mLCO2Kg-1h-1 para os frutos dos sistemas 1 e 2, respectivamente. No final do armazenamento os frutos do sistema 1 apresentaram teores de ácido ascórbico maiores que os do sistema 2. O sistema 1 apresentou, de maneira geral, teores de sólidos solúveis superiores ao sistema 2. No teste sensorial de aparência os provadores preferiram os frutos do sistema 1. Estes frutos foram também os que apresentaram menor incidência de podridão. Para comparar os efeitos dos dois sistemas, isolando-se possíveis variações de qualidade da fruta, mamões do grupo Solo cultivar Golden foram colhidos em pomar comercial no município de Linhares (ES), no estádio 0 de maturação e submetidos aos dois sistemas de embalagem e transporte. Os frutos foram enviados para a CEAGESP, São Paulo (SP), onde foram coletados e levados para o laboratório. O número médio de injúrias por fruto foi de 3,9 no sistema 2 e apenas 1,3 no sistema 1. As lesões encontradas nos dois sistemas estavam localizadas principalmente na região mediana e foram, na maioria, de tamanho pequeno (até 1,5cm). O sistema 2 desenvolveu coloração amarela mais rapidamente, com valor médio do ângulo de cor de 89,6o, enquanto o sistema 1 apresentou valor de 92,8. No sistema 2 os frutos apresentaram firmeza inferior a 20N no terceiro dia de armazenamento e no sistema 1 no nono dia de armazenamento. / The aim of this work was to characterize packaging and transport systems of Solo papaya fruits for the domestic market, and compare them each other, evaluating their consequences in postharvest performance of the papaya transportation from the local production to the wholesale market. A study was carried out in CEAGESP (Companhia de Entrepostos e Armazéns Gerais de São Paulo) to understand the marketing of the product. The papayas commercialized in CEAGESP, stored in cardboard boxes and transported on cooled trucks (system 1) as well as the papayas stored in wooden boxes transported on trucks covered with canvas (system 2) were analyzed in order to identify and characterize the main abiotics and biotics losses from the harvest to the market and to determine the results of each system according to the postharvest procedure. The papayas were taking to the Postharvest Laboratory in Plant Production Department (ESALQ-USP), storage at 23ºC and 80-90% RH, up to full ripening. Solo papaya fruit, Sunrise cultivar, is the most commercialized cultivar in CEAGESP due to its organoleptics characteristics, but it is the Golden papaya the only one which is commercialized in both different packaging and transport systems. The mechanical injuries identified were abrasion, cuts and bruises, in decreasing order of occurrence. It was observed the greatest number of injured fruit in system 2. It was noticed 42% of firmness loss on the third day of storage, for the fruits in system 1 and 63% for the fruits in system 2. On the fourth day of storage, respiratory activity showed average values of 30.4-36.5 mLCO2Kg-1h-1 for fruits in systems 1 and 2, respectively. At the end of the storage, the fruits in system 1 showed higher levels of ascorbic acid than the fruits in system 2. The system 1 showed, in general, higher levels of soluble solids than in system 2. For the appearance sensorial test, the tasters preferred the fruits of the system 1 and were also those who showed less rot incidence. In order to evaluate both systems, the Golden papaya was harvested at early ripening stage from a commercial field in Linhares/ES, and they were submitted to both packaging and transport systems 1 and 2. The fruit was sent to CEAGESP in São Paulo/SP, where they were collected and sent to the laboratory. The average number of injuries per fruit was 3.9 for system 2 and only 1.3 for system 1. The injuries detected for both systems are in the middle region of the fruit and are mostly of small size (up to 1.5 cm). System 2 developed yellow typical color faster, with hue angle 89.6o, whereas system 1 was 92.8. For system 2, the fruits showed firmness under 20N on the third day of storage and on the ninth day for system 1.
2

Caracterização e comparação de sistemas de embalagem e transporte de mamão \'Solo\' destinado ao mercado nacional. / Characterization and comparison of packaging and transport systems of Solo papaya fruits for the domestic market.

Elaine Costa Cerqueira-Pereira 04 August 2009 (has links)
O objetivo do trabalho foi caracterizar sistemas de embalagem e transporte do mamão Solo destinado ao mercado nacional e compará-los entre si, avaliando suas influências no desempenho pós-colheita do mamão transportado do local de produção até o mercado atacadista. Inicialmente foi realizado um estudo de mercado na Companhia de Entrepostos e Armazéns Gerais de São Paulo - CEAGESP para entender a comercialização desse produto. Foram analisados mamões comercializados na CEAGESP acondicionados em caixas de papelão, transportados em caminhão refrigerado (sistema 1) e mamões acondicionados em caixas de madeira, transportados em caminhão coberto com lona (sistema 2) para identificar e caracterizar os principais danos abióticos e bióticos que ocorrem na cadeia de comercialização e para determinar a interferência de cada sistema no desempenho pós-colheita. Os mamões foram levados para o Laboratório de Pós-colheita do Departamento de Produção Vegetal da ESALQUSP mantidos a 23ºC e 80-90% UR, até o completo amadurecimento. O mamão do grupo Solo é o mais comercializado na CEAGESP e dentro desse grupo a cultivar Sunrise devido a suas qualidades organolépticas, mas o mamão Golden é o único comercializado em dois sistemas distintos de embalagem e transporte. As injúrias mecânicas detectadas foram abrasões, cortes e amassamentos em ordem decrescente de ocorrência. Verificou-se maior quantidade de frutos injuriados no sistema 2. A perda de firmeza no terceiro dia de armazenamento foi aproximadamente 42% para os frutos do sistema 1 e de 63% para os frutos do sistema 2. No quarto dia de armazenamento a atividade respiratória assumiu valores médios de 30,4 e 36,5 mLCO2Kg-1h-1 para os frutos dos sistemas 1 e 2, respectivamente. No final do armazenamento os frutos do sistema 1 apresentaram teores de ácido ascórbico maiores que os do sistema 2. O sistema 1 apresentou, de maneira geral, teores de sólidos solúveis superiores ao sistema 2. No teste sensorial de aparência os provadores preferiram os frutos do sistema 1. Estes frutos foram também os que apresentaram menor incidência de podridão. Para comparar os efeitos dos dois sistemas, isolando-se possíveis variações de qualidade da fruta, mamões do grupo Solo cultivar Golden foram colhidos em pomar comercial no município de Linhares (ES), no estádio 0 de maturação e submetidos aos dois sistemas de embalagem e transporte. Os frutos foram enviados para a CEAGESP, São Paulo (SP), onde foram coletados e levados para o laboratório. O número médio de injúrias por fruto foi de 3,9 no sistema 2 e apenas 1,3 no sistema 1. As lesões encontradas nos dois sistemas estavam localizadas principalmente na região mediana e foram, na maioria, de tamanho pequeno (até 1,5cm). O sistema 2 desenvolveu coloração amarela mais rapidamente, com valor médio do ângulo de cor de 89,6o, enquanto o sistema 1 apresentou valor de 92,8. No sistema 2 os frutos apresentaram firmeza inferior a 20N no terceiro dia de armazenamento e no sistema 1 no nono dia de armazenamento. / The aim of this work was to characterize packaging and transport systems of Solo papaya fruits for the domestic market, and compare them each other, evaluating their consequences in postharvest performance of the papaya transportation from the local production to the wholesale market. A study was carried out in CEAGESP (Companhia de Entrepostos e Armazéns Gerais de São Paulo) to understand the marketing of the product. The papayas commercialized in CEAGESP, stored in cardboard boxes and transported on cooled trucks (system 1) as well as the papayas stored in wooden boxes transported on trucks covered with canvas (system 2) were analyzed in order to identify and characterize the main abiotics and biotics losses from the harvest to the market and to determine the results of each system according to the postharvest procedure. The papayas were taking to the Postharvest Laboratory in Plant Production Department (ESALQ-USP), storage at 23ºC and 80-90% RH, up to full ripening. Solo papaya fruit, Sunrise cultivar, is the most commercialized cultivar in CEAGESP due to its organoleptics characteristics, but it is the Golden papaya the only one which is commercialized in both different packaging and transport systems. The mechanical injuries identified were abrasion, cuts and bruises, in decreasing order of occurrence. It was observed the greatest number of injured fruit in system 2. It was noticed 42% of firmness loss on the third day of storage, for the fruits in system 1 and 63% for the fruits in system 2. On the fourth day of storage, respiratory activity showed average values of 30.4-36.5 mLCO2Kg-1h-1 for fruits in systems 1 and 2, respectively. At the end of the storage, the fruits in system 1 showed higher levels of ascorbic acid than the fruits in system 2. The system 1 showed, in general, higher levels of soluble solids than in system 2. For the appearance sensorial test, the tasters preferred the fruits of the system 1 and were also those who showed less rot incidence. In order to evaluate both systems, the Golden papaya was harvested at early ripening stage from a commercial field in Linhares/ES, and they were submitted to both packaging and transport systems 1 and 2. The fruit was sent to CEAGESP in São Paulo/SP, where they were collected and sent to the laboratory. The average number of injuries per fruit was 3.9 for system 2 and only 1.3 for system 1. The injuries detected for both systems are in the middle region of the fruit and are mostly of small size (up to 1.5 cm). System 2 developed yellow typical color faster, with hue angle 89.6o, whereas system 1 was 92.8. For system 2, the fruits showed firmness under 20N on the third day of storage and on the ninth day for system 1.
3

Application des outils de la physique statistique au transport intracellulaire / Application of statistical physics tools to intracellular transport

Klein, Sarah 27 April 2016 (has links)
La plupart des processus dans notre vie quotidienne sont des processus hors équilibre. Un exemple de système hors équilibre est la cellule biologique et le transport qui a lieu dedans. Dans cette thèse ce transport intracellulaire est modélisé par des processus stochastiques. Pour cela deux approches différentes ont été utilisées : d’une part une modélisation explicite de particules actives avec des degrés de liberté internes obtenus expérimentalement, d’autre part une description phénoménologique des effets collectifs, qui est réalisée au moyen de processus d’exclusion.Un des résultats principaux pour le modèle explicite est qu’il est crucial de prendre en compte les fluctuations des forces pour reproduire les caractéristiques principales du mou- vement. Un autre élément important est la prise en considération de l’environnement cellu- laire, qui peut produire des effets non-triviaux, comme par exemple une inversion du sens de déplacement moyen. Pour étudier les effets collectifs il est possible de représenter le mou- vement des particules d’une manière simplifiée, en utilisant un processus d’exclusion avec des particules ayant des états internes. Le désordre sur les taux de saut qui en résulte peut provoquer une condensation dépendant de la densité.Un autre modèle étudié est un processus d’exclusion sur un réseau à deux voies. On suppose que deux types de particules se déplacent dans une géométrie tubulaire, inspirée par les champignons filamenteux. Ces hypothèses définissent un modèle minimal qui présente une transition de phase d’une phase de basse densité vers une phase pulsante caractérisée par des oscillations de densité. / Most processes in our daily life are far from equilibrium. The prime example is a cell and the transport occurring within. In this thesis intracellular transport is modeled by means of stochastic processes. For this, two different approaches are applied: the explicit mod- eling of active particles with internal degrees of freedom with characteristics as they were determined experimentally. And secondly, the collective effects occurring in many particle systems are studied in a phenomenological way by means of exclusion processes.In the explicit model one important result is given by the fact that force fluctuations are essential to capture the relevant motion characteristics. Further, the influence of the cellular environment creates counter-intuitive effects, like a possible inversion of the bias. The motion characteristics can be represented in a coarse-grained manner as an exclusion process for particles with internal states. Due to the resulting disorder in the hopping rates a density-dependent condensation occurs.In a second part, a two-lane exclusion model is studied. Two species in a tubular geometry inspired by filamentous fungi are considered.This can be seen as a minimal model exhibiting a phase transition from a low density phase to an intriguing phase with periodically changing particle densities.
4

Les grans infrastructures de transport i el desenvolupament de la ciutat mitjana. El Tren d'Alta Velocitat a les ciutats de Lleida, Avinyó i Novara

Feliu i Torrent, Jaume 11 February 2005 (has links)
L'objectiu central de la tesi és estudiar els processos que permeten aconseguir un desenvolupament local a llarg termini de les ciutats mitjanes a partir de la implantació d'una gran infrastructura com el Tren d'Alta Velocitat (TAV). Es parteix de la hipòtesi que el desenvolupament local urbà a partir del TAV depèn de factors objectius i de factors subjectius (dels subjectes), uns factors que prenen una forma particular en el desenvolupament de les ciutats mitjanes. La tesi es divideix en una primera part teòrica i segona de més aplicada.Diversos autors han arribat a la conclusió que la relació tradicional que s'ha donat entre les infrastructures de transport i territori parteix d'uns paradigmes deterministes, que s'exemplifiquen amb una relació de "causa-efecte". Per aquest motiu, s'han criticat els estudis sobre els efectes socioeconòmics de les infrastructures de transport, així com el mateix concepte d'"efecte". Aquesta crítica es repeteix els estudis sobre el TAV i les ciutats mitjanes, que arriben a la conclusió que el desenvolupament econòmic no és un fet automàtic i que no es poden predir les conseqüències a mig i llarg termini del TAV.El desenvolupament local a partir del TAV, doncs, estaria relacionat amb tres elements principals. En primer lloc, entendre que la ciutat -i el territori- és un fenomen complex i, com a tal, cal abordar-lo des de la teoria dels sistemes complexos. En segon lloc, la gran infrastructura ha de convertir-se en un recurs endogen (interconnexió amb la xarxa local d'actors i territorialització en el milieu de la ciutat) per a que pugui contribuir al desenvolupament. En tercer lloc, la dinàmica de governance dels actors és primordial, i es divideix en la gestió interna de la xarxa local (projecte local) i la gestió multinivell de les administracions.En base als referents teòrics, es construeix una metodologia per avaluar el grau de desenvolupament local que ha comportat el TAV en tres ciutats mitjanes de l'arc mediterrani europeu, Lleida, Avinyó i Novara, situades respectivament a Espanya, França i Itàlia. La metodologia preveu l'estudi d'aspectes tècnics de la ciutat com els de transport (Posició territorial de la ciutat a partir del TAV, Característiques de l'estació TAV), urbanístics (Model urbanístic a escala municipal/urbana, Model urbanístic a escala de l'estació) i econòmics (Diferents projectes econòmics de la ciutat relacionats amb el TAV). També preveu l'estudi d'aspectes organitzatius externs (Els agents supralocals i els seus projectes, Grau de conflictivitat i cooperació en les relacions dels agents locals i supralocals) i interns (Capacitat de creació d'un projecte de ciutat a partir del TAV, Agents que participen en el projecte local i la seva dinàmica, Àmbit territorial dels projectes). Finalment s'efectua una avaluació del procés i dels resultats del desenvolupament local.Com a conclusió es demostra que el procés de desenvolupament local a partir de les grans infrastructures de transport depèn, en bon part, de la capacitat de governance. Depèn, per un cantó, de la capacitat dels agents locals d'elaborar un projecte de desenvolupament i liderar unes estratègies d'aprofitament i, de l'altre, de la capacitat dels agents del territori (estatals, regionals, locals) de crear aliances i cooperació per planificar la infrastructura de transport. Finalment es presenten un seguit de recomanacions a les ciutats que volen planificar l'arribada del TAV per a que contribueixi a un desenvolupament amb les característiques d'eficàcia, sostenibilitat, productivitat i equitat. / The central goal of this thesis is to study the processes that allow to achieve a long-term local development of medium-sized towns from the implantation of a great infrastructure like High Speed Train (HST). Is started from the hypothesis that the urban local development from the HST depends on objective factors and on subjective factors (of subjects), some factors that take a particular form in the development of medium-sized towns. The thesis is divided into a theoretical part and a second applied part. Several authors have concluded that the traditional relationship between transport infrastructures and territory departs of some deterministic paradigms, such a cause-effect relation. For this motive, they have criticized the studies of socioeconomic effects of transport infrastructures, as well as the concept of "effect". These criticisms are made as well to the relation between HST and medium-sized towns. Many authors conclude that economic development is not an automatic fact and that consequences of HST can not be predicted in half and long term.Local development from the HST, then, would be related to three main elements. First, we need to understand that city and territory are complex phenomenons and, for this, it is necessary to approach them from the theory of complex systems. Second, the great infrastructure has to become an endogenous resource (interconnection with the local network of actors and territorialisation in the milieu of the city) to contribute to development. Third, dynamics of governance between actors is fundamental. It can be divided into internal management of local network (local project) and multilevel management of administrations.With regard to theoretical referents, a methodology is constructed to estimate the degree of local development that has entailed HST in three medium-sized towns of European Mediterranean arch, Lleida, Avingnon and Novara, placed respectively in Spain, France and Italy. The methodology proposes the study of technical aspects of the city like those of transport (Territorial position of the city in HST system, Characteristics of HST station), urban planning (Municipal urban planning model, Urban planning model at scale of station) and economy (Different economic projects of the city related to HST). It also proposes the study of external organizational aspects (Supra-local agents and their projects, Degree of conflictivity and cooperation between local and supra-local agents) and internal (Capacity of creation of a local project from HST, Agents that participate in local project and their dynamics, Territorial area of projects). Finally it is made an evaluation of process and results on local development.As a conclusion it is demonstrated that process of local development from great transport infrastructures depends, basically, on the capacity of governance. It depends, on one side, on the capacity of local agents to elaborate a development project and to lead some strategies and, on the other side, on the capacity of territorial agents (state, region, local) to create alliances and cooperation to planning the transport infrastructure. Finally, some recommendations are presented to the cities that want to plan the arrival of the HST and want to produce development with characteristics of efficiency, sustainability, productivity and equity.

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